Group 4 metal initiators for the controlled stereoselective polymerization of lactide monomers.
نویسندگان
چکیده
Group 4 metal initiators with a tetradentate bis(phenolato) ligand polymerized meso-lactide efficiently under ring-opening to give syndiotactic polylactide. L-Lactide was converted faster than rac-lactide and meso-lactide.
منابع مشابه
Group 4 initiators for the stereoselective ROP of rac-β-butyrolactone and its copolymerization with rac-lactide.
In this paper we demonstrate the utility of Group 4 metals for the well-controlled and stereoselective (syndiotactic) ring opening polymerization (ROP) of rac-β-butyrolactone (BBL) and their ability to form copolymers.
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متن کاملControlled ring-opening polymerization of lactide by group 3 metal complexes
In this review, attention is focused on the use of group 3 metal complexes for the ring-opening polymerization (ROP) of lactide to give polylactides (PLAs). Synthesis of PLAs has been studied intensively due to their biocompatible and biodegradable properties and their potential applications in medical and agricultural fields. ROP of lactide, a cyclic diester of lactic acid, provides PLA. This ...
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The first cationic main group tetrahydroborate complexes are reported. [Ca(BH(4))(THF)(5)][BPh(4)] and the charge neutral (Tp((t)Bu,Me))Ca(BH(4))(THF) are initiators for the living ring opening polymerization of rac-lactide, the latter producing PLA with high levels of heterotactic enrichment. These represent a new class of ROP initiators for main group metals.
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ورودعنوان ژورنال:
- Chemical communications
دوره 47 16 شماره
صفحات -
تاریخ انتشار 2011